So how are the tiles made?... Step 3
The carving is completed and the tile is prepared for the casting of the mold. Notice the rounded bead that frames the tile. The clay beyond that border bead is added to aid in the filling of the mold when the working tiles are pressed. When the pressed tile is removed from the mold, that outer edge of clay is trimmed off. The plastic film under the tile helps keep the clay moist so no shinkage taked place. It also helps in handling the new carving as it can be easily slid or picked up minimizing the risk of damage.